Casing or bearing for valves or other moving parts



Patente Aug. 26, 1924 UNITED STATES JOSEPH H. LEHMAN, OF HASBROUCK HEIGETS, NEW JERSEY.

CASING O'R BEARING FQR VALVES DR OTHER MOVING- PARTS.

Application fl1ed September 27, 1922, Serial N0. 590,810. Renewed November 14, 1923.

T 0 all whom z't may concem:

Be it .known that I, JOSEPH H. LEHMAN, a citizen of the United States, and resident 01 Hasbrouck Heights, in the county of Bergen and State of New Jersey, have invented certain new and useful Improvements in Casings or- Bearings fo1 Va1ves 01 Other Moving Parts, of which the following is a specification.

This invention is an improvernent in bearings for moving parts, and the main object is to provide a proper running fit and substantially uniform olearance under varying eonditions of operation, und particularly varying temperature eonditions.

My invention in its broad aspect is useful in a, wide variety 0f movable members Whie h must be supported 01' guided with very slight clearance, and which are subjected to varying conditions during use.

More specifically my invention is adapted for use with rotary valves subject to varying temperatures which cause expansion and contraction of the parts. For instance, the rotary valve of an internal combustion en gine While operating varies in temperature fro-m that 0f the atmosphere at the start to 01 approximating that of boiling water after the engine has been running f0r a feW minutes. This range is greater in Winter than in summer, and the high limit may under some coriditions exceed that of boiling water if the water be 10W in the jacket 0x the overfiow outlet be closed 01 obstructed to give steam pressure, o1 if the engine is not water coo1ed, or if frietion 01' defective lubrication 1ocally increases ehe temperature.

Eflicienc requires that the valve be Sufficient1y tig t t0 prevent leakage under all operating eonditions, but with ordinary comstruetions the expansion of the valve Will cause it eo bind at high temperature if it fitted properly dt 10W temperature, and will leave it too loose and subject t0 objectionable leakageat 10W temperature if it fitted pr0per1y when heated. This is due in part t0 the fact that the valve and valve easing do not expand at the same rate, and the diameter 0f the aperture 01' valve seat in the casing d0es not follow the diameter of the valve even though they are subjeeted 130 the sarne changes in temperature.

Maixy attempts have been made to over: c0me this difficulty, but so far as 1 knovv, none .is entirely satisfactory. In my improved constructien providie the cas1ng o1 bearing member With a liner 0r liner seetion so mounted and so designed that its expansion under heating inc-reases the diameter of the aperture o1 valve seat at substantial- 'ly the same rate that the same heating effect increases the diameter of the valve m other supported and movable member. Thus there is maintained a substantially uniform running fit or clearanee unde-r all operating conditions.

In my improved constructi-on the diameter of the aperture in the casing is increased 0r decreased by the positive and definite movement 0f a part of the casing upon changes in temperature '0f seid part, and is t0 be distinguished from such constructions es permit an expansion of the va1ve itse1f by a spring pressed casing part which may back off against the spring by the pressure of the valve thereon.

In the accompanying drawings I have shown merely 0ne embodiment 0f my invention, and have shown it as applied to an interna1 eombustion engine of the four-cycle type. In the drawings:

Fig. 1 iS a longitudinal section through the cylinder head showing the valve in intake position.

Fig. 2 is a view similar t0 a portion 0f Fig. 1, but showing the va1ve in exhaust position, and with J;he size 0f sonne of the parts and the clea rances greatly exaggerated t0 facilitate a clear disclosure 0f the parts when 001d 01' contracted, and

Fig. 3 is a view similar t0 Fig. 2, but showing the valve in the position which it occupies at the end of the compression stroke, and with the arts hat 01' expanded.

I have illustrated the invention as applied t0 an internal combusti0n engine having a cylinder 10 provided with a piston 11 and a. water jaeket 12. The cylinder head 13 has n single port 14 which may be Con- 'nected by passages 15 with the intake manifold 16, 01 by a pnssage 17 t0 the exheust manifold 18. The va1ve member 19 has a pair 0:E passages 20, and is rofiated in a clockwise direction by suitable four-to-one gearing, whereby the valve makes a half revolu tion for each complete four-stroke cycle 01? the engine. The valve is shown in wideopen intake position in Fig. l. A rotation t0 the position shown in Fig. 3 closes the port 14 du1ing the compression and power strokes. A further rotation to the position shown in Fig. 2 opens ehe port 14 1b0 the exhaust 1Z' The parts so far described are not new with me, and neither the details thereof n0r the specific mrrangement forr'ns any important art of n1y mvention when the latter is roadly considered.

In the specific form illustrated I carry out my invention by providing a liner 01 liner section 21 forming a. part of the valve casing 01' bearing f0r the valve. This is shown as extending along substantially one-half of the circumferen"e 0r periphery of the valve seat, and diametrically opposite to the port 14. The member 21 may' be a. plate of substantially uniform thickness, and its ends are preferably anchored to the main section 0f the valve casing, whereas the intermediate porrion is free to move radially in respect to the valve. The anchoring of the ends 0f this plateis accomplished in the form illustrated by radially projecting lugs 01' terminal port i0ns 22. These may be clamped t0 the main section 0f the valve casing or the cylinder head, o1 they may be held beneath a eover or top section 23 0f the valve casing.

This member 21 is so constructed and so designed that it expands in the direction of its length by inerease in temperature, but as the end portions are anchored this exv pansion tends to bulge or bow up the intermediate 01 free part. The proportioning of the Parts in respect t0 their relative rates of expansion is such that when the member 21 is expanded to the full extent such as would occur under the highest normal operating conditions of the engine, the valve seat or aperture will be substantially eylindrical, and will be of substantially the sa.me diameter as the diameter 0f the valve itself when the la ter is heated to the same temperature. It Will of course be under-. sbood that the valve diameter and the valve seat diaineter are notexactly the same unden-these conditions as there is provided the slight cl(aarance Which permits the valve 130 turn \f reely. Thisv position of the par,ts is shown in Fig. 3, but I have n0t illuistrated the slight clearance amounting 0 .001 of an inch 01' thereabouts between tlle valve and the valve casing, nor have I illustrated the sli ht clearance which would be left between t epouter surface of the intermediate valve cas1ng section 23, even under the high temperature operating conditions.

When the engine is cold the valve is coutracted to a smaller diameter, but this Same temperature change causes a reduction in the linear distance between the two ends 22 of the member, and the intermediate portion moves downwardl as indicated on exaggerated .scale in i 2. With the arts 'properly designed t e shortening ot the member 21 w1ll be such in proportion to the reduction in-diameter of the valve 19 when the j zarts am 001d, that there will be ortion of the member 21 und thethe same running fit or clearance between the valve 19 and the upper and lower sides of the valve seat, that is, the portion of the casing having the port 14, and the portion 0f the under side 0f the member 21 diametrically opposite to the port 14. There may be increased clearance between the valve and the valve seat at points in the vicinity of the ends 0f the member 21, but this is immaterial as the important point is that the valve shall be held in proper relationship t0 the port 14, and leakage from said port along the sides of the valve will be revented.

1 d0 not wish to be limited to the maintaining of a valve seat diameter exactly equal t0 the valve diameter under all temperature conditions, as satisfactory results Will be secured even though the clearance might be very slightly greater at one temperature than at another, but.I d0- seek to maintain a substantially uniform clearance and the preventing of the movement of the valve away from the p0rt 14 to a sufficient extent 130 permit-leakage at any temperature condition.

During the sure 0n the va ve at the port 14 is very great, but this pressure may be entirely resisted by the memb er 21 and the anchoring 0f the ends o1 the latter. Preferably I provide auxiliary means for resisting the strain 0n the anchorage points and preventing stretdhing of the memb r 21 by the upward pressure 0f the valve 19 during ower strokes of the piston. As shown, I provide a heavy shock spring 24 in the valve casing secti'on 23, and pressmg against the outer surfaee 0f the member 21 substantially diametrically opposite to the ort 14. The pressure of this spring is pre erably substantially equal to the mean upward pressure 0f the valve during running conditions. Thus the member 21 is relieved to a large extent of -any strains or forces tending to change its Position or length except as a result of changed temperature condit1ons.

As the member 21 is in contact with the valve 19, and as both are good heat conduo- .tors, it will be een that an increase 0r decrease 0f the temperature 0f one willcause a cbflesponding and immediate cha.nge in the temperature of the other. This temperature changing will ordinarily be due to the outside atmosphere and the high temperature gases in the cylinder when the engine is running, but it is apparent that it m1ght be due under some cond1tions to other causes. For instance, in case 0f defective lubrication the friction of the valve 19 on the member 21 might generate excessive heat, but this heat Would cause an expansion of the member 21 and prevent the parts from further binding. A red uction in friction with a corresponding drop m temperature would cause the parts Power stroke the upward pres- 1,5os,rea

lo oontract so that under all oonditions the same 01' approximately the same clearance is maintained.

Although I l1ave illustrated and described my invention in connection with a rotary valve or an internal combustion engine, it will be evident that the sa1ne principle is applicable to the bearings or casings for other m'oving arts, particularly where they are subjected to expansion and oontraction as a result of tem rature change.

Having thus esoribed my invention, what I clairn as new and desire to secure by Letters Patent is:

1. In combination, a rotary valve and a valve casing therefor having a liner member extending along a portion of the periphery of the valve, the intermediate ortion of said liner member being movab e radially to' maintain substantially uniform clearance with said valve during variations in the temperature of said valve and said liner momber.

2. In oombination, a valve casing, a rotary valve mounted therein, and a liner member extending along substantially one half the periphery of the valve, the terminal portions of said liner member being anchored and the intermediate portion being free to move radially.

3. In combination, a valve casing, a rotary valve mounted therein, and a liner member extending along substantially one half the periphery of the valve, the terminal portions of said liner rnember being anc hored and the intermediate portion being free 100 move radially, whereby linear expansion to such liner member and radial expansion of said valve rnaintain substantiallyuniform clearance for the valve under all normal temperw ture conditions of operation.

4. In combination, a valve casing, a rotary valve mounted therein, a liner memloer extendirxg along substantially one half the periphery of the valve, the terminal portions of said linear member being anchored and the intermediate Portion being free to move radially, and a resilient rnember normally pressing the intermediate portion of said liner memloer toward said valve.

5. An internal combustion engine having a port, rotary valve for controlling said port, and a valve casing mernber extending along substantially one half the circumference of the valve and diametrically opposite to said port, the terminal portions of said member being anchored and the intermediate portion being movable toward an.ol from said port by temperature changev of saidmemher to maintain uniform clea-rance with said valve under varying temperatre conditions 0 5 tl1e latter.

8. A valve casing having a port and a substantially semi-cy-lindrioal casing momber diametrioally opposite to said port, said oasing member having its ter"rninal portions anchored and its intermediate portion movable radially upon linear expansion and contraotion of the member, whereby the internal diameter of the valve casing inoreases upon increase in temperature.

7. A valve oasing having a port and a casing member diametrically opposite to said port, said casing member having its terminal portions anohored and its interme diate portion movable radially up*on linear expansion and oontraotion of the memloer, whereby the internal diameter of the valve casing increases upon increase in temperature, and a rotary valve within said casing subjected to the same temperature change as said casing mem'ber, the relative rates of expansion, of the valve and member under varying temperature conditions being such as to maintain a substantially uniform clearanoe.

8. In cornbination, a rotary member and a bearing therefor, said bearing including a semi-oylindrical member having its terminal portions anchored and its intermediato ortion movable radially upon ohanges in temperature whereby clearance between said rotary rnember and said casing is rnaintained substantially uniform.

9. In oombination, a casing having an aperture, a rotary member within said aparture, and a member engaging with the periphery of fi:he rotary rnem-ber and adapted t o expand *co increase the diameter oft the aperture upon inorease in temperature to maintain a substantially uniform running fit with said rotary member under varying temperature conolitions.

10. In combination, a rotary valve anol a valve casing there-for having a member engaging with a portion of the periphery of the valve, said portion of saiol member be ing rnovalole radially independently of saiol valve during variations in the temperature of said valve .and saiol member.

11. A valve -oasing having an aperture including a memloer adapted to move radially upon changes in temperature of the momber itself to vary the internal dia-meizer of the casing.

12. A valve oasing having an aperlaure including a menrber adapted to move radially upon changes in temperature of the member ifiself to vary tho internal diameter of the casing', and a rotary member within said aperture, said first mentioned mernber heing rig'icPagainstjgressure there0n by said rotary rnember.

13. In combination a valve oasing having an aperture and a cylindrical rotary valve within said -aperture a portion o:f the poripheral Wall of sa-iol aperture being formed off a member adapted to receive heat from and be mainitained at substanlsially the sarne tem@erature as saiol valve and mouniz'ed to mov e in a radial direction by its own expansion upon being heated.

14. In combination a valve casing having an aperture a-nd a cylindrical rotary valve within said aperture, a Portion of the peripheral Wall of said aperture being formed of a member adapted to receive heat from and be maintained at substantially the same temperature as seid valve and mounted to move in a radial direction by its own expan- 1 sion upon being heated, said. member being rigidly supported to resist radial movement by pressure thereon from thevalve itself.

Signed at New York in the oounty of New York and State of New York this 26th day of September A. D. 1922.

JOSEPH H. LEHMAN. 

